Express each of the following in modulus-argument form, where theta is between zero and pi over 2.

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(a) Express each of the following in modulus-argument form, where $0<\theta<\frac{\pi}{2}$: $$\text{i)}\ 1+i\tan\theta,\quad\text{ii)}\ 1+i\cot\theta,\quad\text{iii)}\ \frac{1}{\sin\theta}+\frac{1}{\cos\theta}i.$$ (b) Hence simplify each of the following: $$\text{i)}\ (1+i\tan\theta)^2,\quad\text{ii)}\ (1+i\cot\theta)^{-3},\quad\text{iii)}\ \frac{1}{\sin\theta}-\frac{1}{\cos\theta}i.$$

I can answer all the questions in my math textbook except for this question. And there are no specific examples of this question in my textbook. Any help is appreciated. THANKS

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Most of your examples are of the form $$a(\cos\theta+i\sin\theta)$$ For example, $$1+i\tan\theta=\frac{1}{\cos\theta}(\cos\theta+i\sin\theta)$$ Can you do the rest? Please tell me if you need any more help.

Note that as $0<\theta<\frac{\pi}{2}$ the values of both $\sin\theta$ and $\cos\theta$ will always be positive.